-For every mount request received from an NFS client,
-.B rpc.mountd
-adds an entry to the
-.B /var/lib/nfs/rmtab
-file. When receiving an unmount request, that entry is removed.
-.P
-However, this file is mostly ornamental. One, the client can continue
-to use the file handle even after calling
-.B rpc.mountd 's
-UMOUNT procedure. And two, if a client reboots without notifying
-.B rpc.mountd ,
-a stale entry will remain in
-.BR rmtab .
+The
+.B rpc.mountd
+daemon registers every successful MNT request by adding an entry to the
+.I /var/lib/nfs/rmtab
+file.
+When receivng a UMNT request from an NFS client,
+.B rpc.mountd
+simply removes the matching entry from
+.IR /var/lib/nfs/rmtab ,
+as long as the access control list for that export allows that sender
+to access the export.
+.PP
+Clients can discover the list of file systems an NFS server is
+currently exporting, or the list of other clients that have mounted
+its exports, by using the
+.BR showmount (8)
+command.
+.BR showmount (8)
+uses other procedures in the NFS MOUNT protocol to report information
+about the server's exported file systems.
+.PP
+Note, however, that there is little to guarantee that the contents of
+.I /var/lib/nfs/rmtab
+are accurate.
+A client may continue accessing an export even after invoking UMNT.
+If the client reboots without sending a UMNT request, stale entries
+remain for that client in
+.IR /var/lib/nfs/rmtab .